Cryptocurrencies can be kept online or offline. If the cryptos are kept on the exchange platforms or other online platforms, it can be lost due to hacks.
So it is important to choose the best wallets that are safe and secure. Please help me in choosing the safest cryptocurrency wallets
That's a good thing you know that storing cryptos in exchange is risky, not only to hacking but also to sudden collapse of the exchange.
If you are looking for the best wallet that are safe and secure, I recommend that you should use a hardware wallet. It is most likely one of the best wallets to store your cryptos with lesser risk than using other wallets.